He said he undervolted his cards. I kind of wonder how much power I'm drawing from the wall. I would assume it's in the mid to high 400 range, but I'm overclocked and over volted
As for the slots, the x1 slot is shorter than the other slots so you'd need a workaround for that with a riser or an extender or something
No way he is getting 50% less power usage with OC and under-voltage. My system without the this card is using 1324W and with it 1513W.
Yes you can use x1 or x4 or x8. No performance penalty. All you need is a riser cable or you need to take back of a pci slot away.